When wiredtiger is running in --groupCollections mode, a prefix must be assigned to each new collection and index to correctly disambiguate and order keys passed to WT sharing the same table.

These prefixes should be persisted (to the catalog or an internal WT table invisible to above layers) as well added to WiredTigerRecordStore and WiredTigerIndex objects at construction. Prefixes must be unique for all live collections and indexes. Reusing a prefix can result in records in different collections colliding. If convenient, a prefix may be used once for a record store and once for an index.

The oplog collection and its index(es) should reside in their own table and not be prefixed.